1. Field of the Invention
The present invention relates to a multilayer molded article comprising a substrate made of a thermoplastic resin and at least two kinds of skin materials laminated on the surface of the substrate wherein the at least two kinds of skin materials include a pair of skin materials adjacent to each other.
2. Description of the Prior Art
Heretofore, multilayer molded articles comprising a substrate made of a thermoplastic resin and skin materials laminated on the surface of the substrate have been used in a wide variety of fields such as automotive interior parts (e.g. door trims and instrument panels) and interior and exterior parts of household appliances.
In the field of such multilayer molded articles, with recent diversification of needs, there is a growing demand for multilayer molded articles comprising a substrate made of a thermoplastic resin and two kinds of skin materials laminated on the surface of the substrate wherein the two skin materials are adjacent to each other.
In a method for obtaining such multilayer molded articles, two parts each of which comprises a substrate made of a thermoplastic resin and a skin material laminated on the surface of the substrate are produced separately by a conventional technique such as injection molding and compression molding, and both parts are jointed together with fitting means or with a screw at edges of the substrates of the parts as illustrated in FIG. 12. In some cases, the two parts are welded together at the edges jointed. In another method, a skin material is laminated on a surface of a substrate made of a thermoplastic resin by injection molding or compression molding and then another skin material is laminated over the foregoing skin material using an adhesive, etc. with the additional skin material partly overlapping with the underlying skin material (FIG. 13).
However, a multilayer molded article produced by the former method is insufficient in joint strength between the substrates because a strong joint between the two kinds of substrates can not be achieved. In the case where the substrates are welded together, there arise problems including deterioration of product's appearance resulting from deformation of the substrates or deformation of the skin materials caused by the heat applied to the substrates because heat is applied directly to the parts molded. When a multilayer molded article is produced by the latter method, there arises a problem of delamination of the skin materials.